Lifting jack



M Mam 31a/vanto@ Nov. 1l 1924.

Patented Nov. 1l, i924.

wield@ SAM SORENSEN, OF H'GUSTON, TEXAS.

LIFTING' JACK.

Application filed` September 8, 1922, Serial No.. 586,977.

T all 'zo/:0m it 771,04/ concern.'

Be it known that I, SAM SonnNsnN, a citizen of the United States, residing at Houston, Harris County, rIeXas, have invented a certain new and useful Improvement in Lifting- Jacks, of which the following is a full, clear, and exact description, suchy as will enable others skilled inl the art to which it appertains to make and `use the same.

My invention relates to lift-ing jacks of the portable type. Itis particularly adapted for ordinary use in lifting of motor vehicles', orv similar loads.

The object of my invention .is to provide a liftingJ jack which may be quickly and easily operated and that will not require a latch of any kind to retain it in adjusted position.

It is alsodesiredto construct a jack which will be simple and strong, and hence not liable'to break or get out of order.

These and other objects and advantages will more clearly appear from the descriptionwhich follows. Referring to the drawings wherein like numerals of reference are appliedr to like parts in all the views, Fig. 1 is a front elevation with a part of the housing lorokenI away for greater clearness. Fig. 2 is a side elevation partly inbroken vertical section. Fig, 3 is a detail of the rack, and Fig. 4lv illustrates the rack-engaging pinion.k

In thevconstruction of my device I have a vertically slidable liftingportion 1, having teeth 2 formed o-n the two opposite sides, thus` providing a rack. The upper end of this lifting rack terminates in ahead 3 formedfof a=rectangular plate as shown.

The rack- 1 is v.mounted within a supporting housing comprising a back plate 6 formed with forwardly extending marginal flanges 5'. Spaced forwardly from the plate 6'1 and; abouty midway of the'- upper end of the housing, and fittingover the forward face ofthe lower portion thereof, is a secondk plate-17; This'fplate is-fwiderat its upper end to iitwithin thel housing and is nan rowed at its lower end, andis secured to the forward portion of thef-housi1ig by means ofbolts 85101' other similar;y means;

Immediately in front ofthe plate 7 I form a 'chamber 9 within which is housed a series of gears. At the upper portion of the housing are two intermeshed gears, 10 and 11. These gears are mounted upon similarI shafts 12. lIhe gears 10' and 11 are fixed upon the shafts 12 and the said shafts are extended through the plate 7 and? the housing et to form a bearing therein; The shafts are so positioned as to project through plate 7 and to tit within the semicylindrical recesses 14 between the adjacent teeth of the rack 1. The recesses 14 are approximately semi-cylindricah yet somewhat elongated so as to allow a slight space at either side of the shaft 12 fitted therein. As shown particularly in Fig.' @1, the sliaft 12 is hollowed out centrally'into tubular shape, and one side thereof is'V out away so as to leave a crescent shaped portion l5 to tit against the rack 1.

There are also two lower gears 10 and 11 exactly similar in construction to the two upper gears, and the shafts 12 upon which they are mounted are also formed into pinions 1G adapted to cooperate with the teeth of the rack 2. As will he noted iu Fig. B theposition of the pinions relative to the rack, arereversed in the lower shafts over that of the upper shaft, sothat while the upper pinions are turned into the conver; side ofthe crescent fitting within the notch or recess 1st between the adjacent teeth, the lower pinions are contacting with the teeth of the rack with the concave side of the pinion.

rih'e two sets of pinions are operated through the gears 10, 10', 11 and 11 4by means of an operating' gear 17, mounted' in the housing midway between theA upper and lower sets of gears and meshing with those on one side of the housing-only. The gear 17 is mounted upon an operating shaft' 18 which is supported at its Linner end within the plate-7 and on the. outer portion there-y of within the plate19, whichA acts as a cover plate for the forward face of the upperipori tion of thehousing. The gear 17 is mounted rigidly thereon midway between the plates 7 andi19,vand` is thereby` housedv and' pro"- tected against dust and dirt` Therotation of the shaft 18 in either direction will cause the simultaneous rotation` ofthe two gears 10 and 10, and by that meansk will also-rolate'th'ef'tw'o gears;y 11l and 11". It will be noted that by this arrangement the two gears 10 and 10,will be rotated in the-'same direction and the two gears l1V and 11 will be rotated in the same direction, but in the opposite direction from the gears 10 and 10 If desired, a universal joint 2O may be formed on the shaft 18 and a crank 21 secured to said joint so that the rotationV of the crank 21. will thereby rotate the shaft- 18, and adjustment in the position of the crank 21 may be made to accommodate dif- I almost square and may be therefore placed in position.y at almost any desired angle and work equally well in all positions.

In the operation of my device the jack is placed in position beneath the axle of the f car, or any other desired load to be lifted,

and when thus inposition the turning of the crank 21 will cause the rotation of the different gears, in the manner described. lVith special reference to Fig. 3 it will be noted that the rotation of the shafts 12 will cause the pinions 16 thereon to alternately engage the teeth on the rack 1 as shown at the lower end of the said ligure, and `to raise or lower the said rack according to the direction of rotation of the cra-nk. The upper pinions will be in the opposite position with the convex side fitting within the recesses 14. It will therefore be apparent that as the gears are rotated the rack will be raised or lowered .in the desired direction, and when the load has been raised to the desired point the load will be sustained in that position automatically through the pinions 16. In the position shown in Fig. .3 the upper pinions will be in supporting position and will automatically retain the rack in that position. There will be no tendency of the weight orrload upon the rack to cause the rotation of the pinions 16 due to the shape thereof. It

. will therefore be observed that the? load may maintain itself in adjusted position.

be very readily raised and lowered, and the action of the tool may be stopped at any desired point, and will automatically Y When it is desired to release the load, the rotation ofthe crank in the opposite direction will immediately cause the movement of the supporting rack in the opposite direct-ion and lower the load and release the jack. The advantages of this tool will be apparent to one skilled in the art without further description.

What I claim as new` and desire to pro Y tect by Letters Patent is:

1. In a lifting jack, a supporting housing, a rack slidable vertically therein, teeth on each side of said rack shaped to provide approximately semicylindrical recesses between adjacent teeth, a pinion formed with a crescent-shaped portion adapted to lit on its outer side within each said recesses and when rotated to engage said teeth on its opposite side, and means to rotatesaid pinion,

2. In a lifting jack, a supporting housing, a rack slidable vertically therein, teeth on two sides of said rack having approximately semicircular recesses between adjacent teeth, pinions having crescent-shaped portions coacting with said rack to raise or lower the same when said pinions are rotated, gears on said pinions, and means to operate said gears. l

In a lifting jack, a supporting housing, a longitudinally slidable rack in said hous ing, teeth on opposite sides of said rack, a plurality of sets of opposite crescentshaped pinions shaped to fit between said teeth on their convex sides and' to engage said teeth with their concave sides when rotated, said sets of pinions arranged so that when one set presents its concave portion to the rack, another set will present its convex portion to the rack, and means to rotate said pinions simultaneously.

4. In a lifting jack, a supporting housing, a vertically slidable, liftingV rack in said housing, teeth on one side of said rack having approximately semcylindrical recesses between them, upper and lower crescent-shaped pinions shaped to fit loosely within said recesses on their convex sides.-

and to engage said teeth with their concavesides when rotated, the upper pinion being arranged to engage said teeth when the lower pinion is disengaged and means to rotate said pinions simultaneously in the same direction.

5. In a lifting jack, the combination of a supporting housing, a lifting rack slidable therein and having teeth thereon, upper and lower lifting elements engaging said teeth and adapted in one posit-ion to support said rack and when rotated from said position to engage said teeth to move said rack, and means to rotate said elements, one element being in supporting position when the other is in lifting position.

6. In a jack, a lifting rack, a support therefor, teeth on said rack, crescent-shaped pinions engaging said rack, and means to rotate said pinions simultaneously in the same direction, said pinions being adapted to support said rack when the convex side of the pinion engages the rack, one or the other of said pinions being in supporting position at all times. y

In testmony whereof, I hereunto affixed my signature, this the 2nd day of September, A. D. 1922. g

SAM SORENSEN. 

